package com.westcom.vulb.common;

import android.content.Context;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.ImageView;

public class TouchImageView extends ImageView {

 Matrix matrix;

 // We can be in one of these 3 states

 static final int NONE = 0;

 static final int DRAG = 1;

 static final int ZOOM = 2;

 int mode = NONE;



 // Remember some things for zooming

 PointF last = new PointF();

 PointF start = new PointF();

 float minScale = 1f;

 float maxScale = 3f;

 float[] m;

 int viewWidth, viewHeight;
 static final int CLICK = 3;
 float saveScale = 1f;
 protected float origWidth, origHeight;
 int oldMeasuredWidth, oldMeasuredHeight;
 ScaleGestureDetector mScaleDetector;
 Context context;

 public TouchImageView(Context context) {

     super(context);

     sharedConstructing(context);

 }
 public TouchImageView(Context context, AttributeSet attrs) {

     super(context, attrs);

     sharedConstructing(context);

 }
 private void sharedConstructing(Context context) {

     super.setClickable(true);

     this.context = context;

     mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());

     matrix = new Matrix();

     m = new float[9];

     setImageMatrix(matrix);

     setScaleType(ScaleType.MATRIX);
     setOnTouchListener(new OnTouchListener() {
         @Override

         public boolean onTouch(View v, MotionEvent event) {
             mScaleDetector.onTouchEvent(event);
             PointF curr = new PointF(event.getX(), event.getY());
             switch (event.getAction()) {

                 case MotionEvent.ACTION_DOWN:
                     last.set(curr);
                     start.set(last);
                     mode = DRAG;
                     break;
                 case MotionEvent.ACTION_MOVE:

                     if (mode == DRAG) {

                         float deltaX = curr.x - last.x;

                         float deltaY = curr.y - last.y;

                         float fixTransX = getFixDragTrans(deltaX, viewWidth, origWidth * saveScale);

                         float fixTransY = getFixDragTrans(deltaY, viewHeight, origHeight * saveScale);

                         matrix.postTranslate(fixTransX, fixTransY);

                         fixTrans();

                         last.set(curr.x, curr.y);
                     }
                     break;
                 case MotionEvent.ACTION_UP:
                     mode = NONE;

                     int xDiff = (int) Math.abs(curr.x - start.x);

                     int yDiff = (int) Math.abs(curr.y - start.y);

                     if (xDiff < CLICK && yDiff < CLICK)

                         performClick();

                     break;



                 case MotionEvent.ACTION_POINTER_UP:

                     mode = NONE;

                     break;

             }
             setImageMatrix(matrix);

             invalidate();

             return true; // indicate event was handled

         }
     });

 }
 public void setMaxZoom(float x) {

     maxScale = x;

 }

 private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {

     @Override

     public boolean onScaleBegin(ScaleGestureDetector detector) {

         mode = ZOOM;

         return true;

     }



     @Override

     public boolean onScale(ScaleGestureDetector detector) {

         float mScaleFactor = detector.getScaleFactor();

         float origScale = saveScale;

         saveScale *= mScaleFactor;

         if (saveScale > maxScale) {

             saveScale = maxScale;

             mScaleFactor = maxScale / origScale;

         } else if (saveScale < minScale) {

             saveScale = minScale;

             mScaleFactor = minScale / origScale;

         }
         if (origWidth * saveScale <= viewWidth || origHeight * saveScale <= viewHeight)

             matrix.postScale(mScaleFactor, mScaleFactor, viewWidth / 2, viewHeight / 2);

         else

             matrix.postScale(mScaleFactor, mScaleFactor, detector.getFocusX(), detector.getFocusY());
         fixTrans();

         return true;

     }

 }
 void fixTrans() {

     matrix.getValues(m);

     float transX = m[Matrix.MTRANS_X];

     float transY = m[Matrix.MTRANS_Y];
     float fixTransX = getFixTrans(transX, viewWidth, origWidth * saveScale);

     float fixTransY = getFixTrans(transY, viewHeight, origHeight * saveScale);
     if (fixTransX != 0 || fixTransY != 0)

         matrix.postTranslate(fixTransX, fixTransY);

 }

 float getFixTrans(float trans, float viewSize, float contentSize) {

     float minTrans, maxTrans;

     if (contentSize <= viewSize) {

         minTrans = 0;

         maxTrans = viewSize - contentSize;

     } else {

         minTrans = viewSize - contentSize;

         maxTrans = 0;

     }
     if (trans < minTrans)

         return -trans + minTrans;

     if (trans > maxTrans)

         return -trans + maxTrans;

     return 0;

 }
 float getFixDragTrans(float delta, float viewSize, float contentSize) {

     if (contentSize <= viewSize) {

         return 0;

     }

     return delta;

 }
 @Override

 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

     super.onMeasure(widthMeasureSpec, heightMeasureSpec);

     viewWidth = MeasureSpec.getSize(widthMeasureSpec);

     viewHeight = MeasureSpec.getSize(heightMeasureSpec);
     //

     // Rescales image on rotation

     //

     if (oldMeasuredHeight == viewWidth && oldMeasuredHeight == viewHeight

             || viewWidth == 0 || viewHeight == 0)

         return;

     oldMeasuredHeight = viewHeight;

     oldMeasuredWidth = viewWidth;
     if (saveScale == 1) {

         //Fit to screen.

         float scale;
         Drawable drawable = getDrawable();

         if (drawable == null || drawable.getIntrinsicWidth() == 0 || drawable.getIntrinsicHeight() == 0)

             return;

         int bmWidth = drawable.getIntrinsicWidth();

         int bmHeight = drawable.getIntrinsicHeight(); 

         Log.d("bmSize", "bmWidth: " + bmWidth + " bmHeight : " + bmHeight);

         float scaleX = (float) viewWidth / (float) bmWidth;

         float scaleY = (float) viewHeight / (float) bmHeight;

         scale = Math.min(scaleX, scaleY);

         matrix.setScale(scale, scale);

         // Center the image

         float redundantYSpace = (float) viewHeight - (scale * (float) bmHeight);

         float redundantXSpace = (float) viewWidth - (scale * (float) bmWidth);

         redundantYSpace /= (float) 2;

         redundantXSpace /= (float) 2;

         matrix.postTranslate(redundantXSpace, redundantYSpace);

         origWidth = viewWidth - 2 * redundantXSpace;

         origHeight = viewHeight - 2 * redundantYSpace;

         setImageMatrix(matrix);
     }
     fixTrans();
 }

}
